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Sorry I can't answer your question about carrots in pots. But I have experience in sowing them directly in the gound in Brooks, Ga.

My first sowing last year was on carrot week about April 15. They popped right up in about 3-5 days, got about a couple of inches tall and sat there all summer doing nothing the rest of the summer. In the fall they took off and I pulled a mess of carrots. Last spring was so short they did not have time to produce anything before the hot weather got here.

This year I decided not to wait for carrot week and started planting them early. I planted two squares on 2/10/13. They have just now sprouted. I guess it was still a little cold for them that early. I planted two more squares on 2/24/13. They have not yet germinated. I planted another two squares this morning. I hope they germinate a little faster than the earlier ones. I have a feeling that the latest planted ones will produce almost about the same time as the earliest planted carrots.

Basic information: Carrots can be sown outdoors 3 weeks before your last expected frost. I would transplant any seedlings the same time and very gently to not disturb the roots.Edited to add: I would also loosen the soil in the square down as far as you can, up to 12" or so, to make it easier for the carrots to spread their roots without rocks impeding.

@quiltbea wrote:Basic information: Carrots can be sown outdoors 3 weeks before your last expected frost. I would transplant any seedlings the same time and very gently to not disturb the roots.

In the South, carrots work better as a fall crop. I sow in August and have nice fresh carrots all winter. I sowed a spring crop the first week of February, but it will be touch and go to get them to produce before hot weather comes. Sometimes here it goes from winter to summer without much spring. If spring is extended, MAYBE I'll get some spring carrots.

The biggest problem with sowing in August is getting germination. It's usually mighty hot, and it dries out very fast. I water 2-3 times a day until the carrots show, then drop back to once a day. But sometimes that doesn't even work, especially if it's running near 100 degrees every day.

@Pollinator wrote:The biggest problem with sowing in August is getting germination. It's usually mighty hot, and it dries out very fast. I water 2-3 times a day until the carrots show, then drop back to once a day. But sometimes that doesn't even work, especially if it's running near 100 degrees every day.

Pollinator, try priming your carrot seeds first this fall and see if it makes a difference with germination rates. I picked up on the tip from this blog post: Growing Carrots with Character. Here's the pertinent excerpt:

Carrot seeds are naturally slow germinators, but you can speed things up a bit by priming the seeds indoors. Starting three to four days before you plan to sow them, soak carrot seeds in water for an hour, and then transfer them to a damp paper towel. Fold to enclose the seeds, then put inside an airtight container. Keep at room temperature. Plant the primed seeds within five days. I find that it is seldom necessary to prime seeds sown in spring, my rainiest season, but priming carrot seeds is tremendously helpful in summer, when I'm planting carrots for fall.

@gwennifer wrote:Carrot seeds are naturally slow germinators, but you can speed things up a bit by priming the seeds indoors. Starting three to four days before you plan to sow them, soak carrot seeds in water for an hour, and then transfer them to a damp paper towel. Fold to enclose the seeds, then put inside an airtight container. Keep at room temperature. Plant the primed seeds within five days. I find that it is seldom necessary to prime seeds sown in spring, my rainiest season, but priming carrot seeds is tremendously helpful in summer, when I'm planting carrots for fall.